1. Thermal Energy Research Institute, Automation and Energy Resources College, Tianjin University, 92 Weijin Road Nankai District, Tianjin 300072, P. R. China,
2. Tianjin Internal Combustion Engine Research Institute, Tianjin University, Tianjin 300072, P. R. China
3. South China University of Engineering, Wushan Guangzhao 510640, P. R. China